:root {
  color-scheme: light;
  --color-surface: #ffffff;
  --color-surface-muted: #f6f9ff;
  --color-border: rgba(61, 174, 250, 0.18);
  --color-text-strong: #0f172a;
  --color-text: #23272f;
  --color-text-muted: #5c5c6b;
  --color-primary: #3DAEFA;
  --color-primary-contrast: #ffffff;
  --navbar-bg: linear-gradient(135deg, #34b3ff, #3DAEFA 45%, #2b86ff);
  --navbar-text: #ffffff;
  --navbar-hover: rgba(255, 255, 255, 0.16);
  --navbar-shadow: 0 6px 22px rgba(41, 125, 255, 0.18);
  --control-bg: #ffffff;
  --control-border: #dbeafe;
}

:root.dark-mode {
  color-scheme: dark;
  --color-surface: rgba(15, 23, 42, 0.92);
  --color-surface-muted: rgba(30, 41, 59, 0.7);
  --color-border: rgba(148, 163, 184, 0.28);
  --color-text-strong: #f8fafc;
  --color-text: #e2e8f0;
  --color-text-muted: #94a3b8;
  --color-primary: #38bdf8;
  --color-primary-contrast: #0b1120;
  --navbar-bg: linear-gradient(135deg, #0b1120, #12233e 55%, #1f3b71);
  --navbar-text: #e2e8f0;
  --navbar-hover: rgba(148, 163, 184, 0.22);
  --navbar-shadow: 0 12px 30px rgba(2, 6, 23, 0.45);
  --control-bg: rgba(30, 41, 59, 0.68);
  --control-border: rgba(148, 163, 184, 0.35);
}

html {
  min-height: 100%;
  background-color: var(--color-surface-muted);
}

body {
  color: var(--color-text);
  transition: background-color 0.28s ease, color 0.28s ease;
  min-height: 100vh;
  background-color: var(--color-surface-muted);
}

html.dark-mode {
  background-color: #0b1120;
}

body.dark-mode {
  background-color: #0b1120;
}

body.dark-mode::selection {
  background: rgba(56, 189, 248, 0.35);
  color: #f8fafc;
}

input,
textarea,
select,
button {
  transition: background-color 0.2s ease, color 0.2s ease, border-color 0.2s ease, box-shadow 0.2s ease;
}

body.dark-mode input,
body.dark-mode textarea,
body.dark-mode select {
  background: var(--control-bg);
  color: var(--color-text);
  border-color: var(--control-border);
}

body.dark-mode input::placeholder,
body.dark-mode textarea::placeholder {
  color: var(--color-text-muted);
}

/* ===== NAVBAR (Global) ===== */
body.has-navbar {
  padding-top: 64px; /* 네비바 높이만큼 컨텐츠 내려앉게 */
}

.navbar {
  position: fixed;
  top: 0; left: 0; right: 0;
  height: 64px;
  display: flex; align-items: center; justify-content: space-between;
  padding: 0 24px;
  gap: 14px;
  background: var(--navbar-bg);
  color: var(--navbar-text);
  z-index: 2100; /* 다른 고정요소보다 위 */
  box-shadow: var(--navbar-shadow);
  -webkit-backdrop-filter: saturate(1.2) blur(4px);
  backdrop-filter: saturate(1.2) blur(4px);
}

/* 브랜드는 줄어들지 않게 고정 */
.navbar .brand {
  flex: 0 0 auto;
  font-weight: 800;
  letter-spacing: .2px;
  text-decoration: none;
  color: var(--navbar-text);
  font-size: 18px;
}

/* 오른쪽 그룹: HTML에서 right-group 또는 nav-right 둘 다 인식 */
.right-group,
.nav-right {
  display: flex;
  align-items: center;
  gap: 10px;
  flex-wrap: nowrap;   /* 줄바꿈 방지 */
  min-width: 0;        /* 내부 요소 ellipsis 허용 */
  flex: 1 1 auto;      /* 남은 공간 사용 */
  justify-content: flex-end;
}

/* 링크 묶음도 한 줄 유지 */
#nav-links {
  display: flex;
  align-items: center;
  gap: 8px;
  flex-wrap: nowrap;
  min-width: 0;
}

#nav-links a {
  color: var(--navbar-text);
  text-decoration: none;
  margin-left: 18px;
  font-weight: 600;
  font-size: 14px;
  padding: 8px 12px;
  border-radius: 10px;
  transition: background .15s ease, transform .08s ease;
  white-space: nowrap; /* 링크 텍스트 줄바꿈 방지 */
}

#nav-links a:hover {
  background: var(--navbar-hover);
  transform: translateY(-1px);
}

/* 닉네임: 한 줄 유지 + 길면 말줄임 */
.user-info {
  display: inline-flex;
  align-items: center;
  max-width: 240px;     /* 필요 시 조정 */
  min-width: 0;
  padding: 8px 12px;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  color: var(--navbar-text);
  font-weight: 700;
  opacity: .95;
  margin-left: 6px;
  border-radius: 10px;
  transition: background .15s ease, transform .08s ease;
}

.user-info:hover {
  background: var(--navbar-hover);
  transform: translateY(-1px);
}

.user-info a {
  display: inline-block;
  max-width: 100%;
  color: inherit;
  text-decoration: none;
  font-weight: inherit;
  overflow: hidden;
  text-overflow: ellipsis;
}

.user-info a:hover,
.user-info a:focus,
.user-info a:active,
.user-info a:visited {
  color: inherit;
}

.theme-toggle {
  appearance: none;
  border: 1px solid rgba(255, 255, 255, 0.4);
  background: transparent;
  color: var(--navbar-text);
  width: 36px;
  height: 36px;
  border-radius: 50%;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: background 0.15s ease, color 0.15s ease, border-color 0.15s ease, transform 0.1s ease;
}

.theme-toggle:hover {
  background: rgba(255, 255, 255, 0.16);
  transform: translateY(-1px);
}

.theme-toggle:active {
  transform: scale(0.94);
}

body.dark-mode .theme-toggle {
  border-color: rgba(148, 163, 184, 0.48);
}

body.dark-mode .theme-toggle:hover {
  background: rgba(148, 163, 184, 0.2);
}

.theme-toggle__icon {
  font-size: 18px;
  line-height: 1;
}

/* ===== DARK THEME OVERRIDES ===== */
body.dark-mode #nav-links a:hover {
  background: var(--navbar-hover);
}

body.dark-mode .navbar .brand,
body.dark-mode .navbar .brand a,
body.dark-mode .user-info {
  color: var(--navbar-text);
}

body.dark-mode a {
  color: #93c5fd;
}

body.dark-mode a:hover {
  color: #bfdbfe;
}

body.dark-mode .container,
body.dark-mode .profile-header,
body.dark-mode .info-card,
body.dark-mode .activity-list,
body.dark-mode .submission-card,
body.dark-mode .card,
body.dark-mode .modal,
body.dark-mode .table-wrapper {
  background-color: var(--color-surface);
  color: var(--color-text);
  border-color: var(--color-border);
  box-shadow: 0 18px 42px rgba(2, 6, 23, 0.42);
}

body.dark-mode .submission-card__body .info-row,
body.dark-mode .submission-card__meta {
  background-color: transparent;
  border-color: var(--color-border);
}

body.dark-mode .profile-avatar {
  background: linear-gradient(135deg, rgba(56, 189, 248, 0.45) 0%, rgba(14, 165, 233, 0.6) 100%);
  color: #f8fafc;
}

body.dark-mode h1,
body.dark-mode h2,
body.dark-mode h3,
body.dark-mode h4,
body.dark-mode h5,
body.dark-mode h6,
body.dark-mode strong,
body.dark-mode .profile-name {
  color: var(--color-text-strong);
}

body.dark-mode .profile-moto,
body.dark-mode .info-label,
body.dark-mode .activity-date,
body.dark-mode .stat-label,
body.dark-mode .meta-item .label,
body.dark-mode .label {
  color: var(--color-text-muted);
}

body.dark-mode .info-value,
body.dark-mode .activity-title,
body.dark-mode .stat-value,
body.dark-mode .submission-card__title h2,
body.dark-mode .meta-item .value,
body.dark-mode .value {
  color: var(--color-text);
}

body.dark-mode .activity-item {
  background: var(--color-surface-muted);
  border-color: rgba(148, 163, 184, 0.2);
  box-shadow: none;
}

body.dark-mode .info-row {
  border-color: rgba(148, 163, 184, 0.2);
  background: transparent;
}

body.dark-mode .value.code {
  color: #bfdbfe;
}

body.dark-mode .meta-item {
  color: var(--color-text);
}

body.dark-mode .badge {
  background: rgba(59, 130, 246, 0.24);
  color: #bfdbfe;
}

body.dark-mode .badge-correct {
  background: rgba(22, 163, 74, 0.28);
  color: #bbf7d0;
}

body.dark-mode .badge-wrong {
  background: rgba(220, 38, 38, 0.28);
  color: #fecaca;
}

body.dark-mode .badge.difficulty-hard {
  background: rgba(239, 68, 68, 0.28);
  color: #fecaca;
}

body.dark-mode .badge.difficulty-medium {
  background: rgba(234, 179, 8, 0.28);
  color: #fef3c7;
}

body.dark-mode .badge.difficulty-easy {
  background: rgba(16, 185, 129, 0.28);
  color: #bbf7d0;
}

body.dark-mode .btn {
  background: var(--color-primary);
  color: var(--color-primary-contrast);
  border-color: transparent;
}

body.dark-mode .btn:hover {
  background: #0ea5e9;
}

body.dark-mode .btn-secondary {
  background: transparent;
  color: var(--color-primary);
  border-color: var(--color-primary);
}

body.dark-mode .btn-secondary:hover {
  background: rgba(56, 189, 248, 0.12);
}

/* 반응형: 공간 줄어들 때 닉네임 최대폭 축소 */
@media (max-width: 700px) {
  .navbar { padding: 0 14px; height: 54px; }
  .navbar .brand { font-size: 16px; }
  #nav-links a { margin-left: 10px; font-size: 13px; padding: 6px 8px; }
  .user-info { max-width: 140px; font-size: 13px; }
}